1h4t: Difference between revisions
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[[Image:1h4t.gif|left|200px]]<br /><applet load="1h4t" size=" | [[Image:1h4t.gif|left|200px]]<br /><applet load="1h4t" size="350" color="white" frame="true" align="right" spinBox="true" | ||
caption="1h4t, resolution 2.9Å" /> | caption="1h4t, resolution 2.9Å" /> | ||
'''PROLYL-TRNA SYNTHETASE FROM THERMUS THERMOPHILUS COMPLEXED WITH L-PROLINE'''<br /> | '''PROLYL-TRNA SYNTHETASE FROM THERMUS THERMOPHILUS COMPLEXED WITH L-PROLINE'''<br /> | ||
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==About this Structure== | ==About this Structure== | ||
1H4T is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Thermus_thermophilus Thermus thermophilus] with ZN and PRO as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Proline--tRNA_ligase Proline--tRNA ligase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=6.1.1.15 6.1.1.15] Known structural/functional Sites: <scene name='pdbsite=AC1:Zn Binding Site For Chain A'>AC1</scene>, <scene name='pdbsite=AC2:Zn Binding Site For Chain B'>AC2</scene>, <scene name='pdbsite=AC3:Zn Binding Site For Chain C'>AC3</scene>, <scene name='pdbsite=AC4:Zn Binding Site For Chain D'>AC4</scene>, <scene name='pdbsite=AC5:PRO Binding Site For Chain A'>AC5</scene>, <scene name='pdbsite=AC6:PRO Binding Site For Chain B'>AC6</scene>, <scene name='pdbsite=AC7:PRO Binding Site For Chain C'>AC7</scene> and <scene name='pdbsite=AC8:PRO Binding Site For Chain D'>AC8</scene>. Full crystallographic information is available from [http:// | 1H4T is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Thermus_thermophilus Thermus thermophilus] with <scene name='pdbligand=ZN:'>ZN</scene> and <scene name='pdbligand=PRO:'>PRO</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Proline--tRNA_ligase Proline--tRNA ligase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=6.1.1.15 6.1.1.15] Known structural/functional Sites: <scene name='pdbsite=AC1:Zn+Binding+Site+For+Chain+A'>AC1</scene>, <scene name='pdbsite=AC2:Zn+Binding+Site+For+Chain+B'>AC2</scene>, <scene name='pdbsite=AC3:Zn+Binding+Site+For+Chain+C'>AC3</scene>, <scene name='pdbsite=AC4:Zn+Binding+Site+For+Chain+D'>AC4</scene>, <scene name='pdbsite=AC5:PRO+Binding+Site+For+Chain+A'>AC5</scene>, <scene name='pdbsite=AC6:PRO+Binding+Site+For+Chain+B'>AC6</scene>, <scene name='pdbsite=AC7:PRO+Binding+Site+For+Chain+C'>AC7</scene> and <scene name='pdbsite=AC8:PRO+Binding+Site+For+Chain+D'>AC8</scene>. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1H4T OCA]. | ||
==Reference== | ==Reference== | ||
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[[Category: class ii aminoacyl-trna synthetase]] | [[Category: class ii aminoacyl-trna synthetase]] | ||
''Page seeded by [http:// | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Feb 3 09:46:21 2008'' | ||
Revision as of 10:46, 3 February 2008
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PROLYL-TRNA SYNTHETASE FROM THERMUS THERMOPHILUS COMPLEXED WITH L-PROLINE
OverviewOverview
We describe the recognition by Thermus thermophilus prolyl-tRNA synthetase, (ProRSTT) of proline, ATP and prolyl-adenylate and the sequential, conformational changes occurring when the substrates bind and the, activated intermediate is formed. Proline and ATP binding cause, respectively conformational changes in the proline binding loop and motif, 2 loop. However formation of the activated intermediate is necessary for, the final conformational ordering of a ten residue peptide ("ordering, loop") close to the active site which would appear to be essential for, functional tRNA 3' end binding. These induced fit conformational changes, ensure that the enzyme is highly specific for proline activation and, aminoacylation. We also present new structures of apo and AMP bound, histidyl-tRNA synthetase (HisRS) from T. thermophilus which we compare to, our previous structures of the histidine and histidyl-adenylate bound, enzyme. Qualitatively, similar results to those observed with T., thermophilus prolyl-tRNA synthetase are found. However histidine binding, is sufficient to induce the co-operative ordering of the topologically, equivalent histidine binding loop and ordering loop. These two examples, contrast with most other class II aminoacyl-tRNA synthetases whose pocket, for the cognate amino acid side-chain is largely preformed. T., thermophilus prolyl-tRNA synthetase appears to be the second class II, aminoacyl-tRNA synthetase, after HisRS, to use a positively charged amino, acid instead of a divalent cation to catalyse the amino acid activation, reaction.
About this StructureAbout this Structure
1H4T is a Single protein structure of sequence from Thermus thermophilus with and as ligands. Active as Proline--tRNA ligase, with EC number 6.1.1.15 Known structural/functional Sites: , , , , , , and . Full crystallographic information is available from OCA.
ReferenceReference
A succession of substrate induced conformational changes ensures the amino acid specificity of Thermus thermophilus prolyl-tRNA synthetase: comparison with histidyl-tRNA synthetase., Yaremchuk A, Tukalo M, Grotli M, Cusack S, J Mol Biol. 2001 Jun 15;309(4):989-1002. PMID:11399074
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